A number of actuators are provided in an internal combustion engine for a vehicle. A control device for an internal combustion engine controls the internal combustion engine by performing coordinated manipulation of those actuators. Control relating to the plurality of actuators includes intake air amount control. Controlling an intake air amount is performed mainly by a throttle disposed in an intake passage. However, when an intake valve is provided with a variable valve timing mechanism (hereinafter, VVT), the intake air amount is affected by not only an opening of the throttle but also an operating state of the VVT. Therefore, as described in JP-A No. 2004-245082, for example, conventional control devices for an internal combustion engine have identified each operable range of the throttle and the VVT and have determined optimum actuator operating amounts for realizing a target intake air amount in the range.
However, the VVT is not the only actuator other than the throttle to be taken into account in controlling of an intake air amount. In order to accurately control the intake air amount by the throttle, it is better to take into account all the actuators of which the operating states affect a relationship between an intake air amount and an intake pipe pressure. Such actuators include a waste gate valve (hereinafter, WGV), a variable lift amount mechanism that varies a lift amount of the intake valve, and so on. Application to these actuators is not mentioned in the above patent document.
In addition, it is conceivable to perform adaptation of command values for all the actuators including the throttle for each operational condition including an engine speed and an intake air amount to map the command values. However, in order to accurately control the intake air amount, it is necessary to perform adaptation for the actuator command values not only in steady states but also in transient states. Performing adaptation in transient states is difficult and requires significant man-hours. Therefore, it is far from realistic to map the command values for all the actuators.